Fixes (web): Optimized search page style and functionality #3221 (#9627)

### What problem does this PR solve?

Fixes (web): Optimized search page style and functionality #3221

- Updated search page and view title styles
- Modified dataset list and multi-select control styles
- Optimized text field and button styles
- Updated filter button icons
- Adjusted metadata filter styles
- Added default descriptions for the smart assistant

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

web/src/pages/dataset/dataset/parsing-status-cell.tsx

@@ -27,7 +27,7 @@ const IconMap = {
   [RunningStatus.UNSTART]: (
     <div className="w-0 h-0 border-l-[10px] border-l-accent-primary border-t-8 border-r-4 border-b-8 border-transparent"></div>
   ),
-  [RunningStatus.RUNNING]: <CircleX size={14} />,
+  [RunningStatus.RUNNING]: <CircleX size={14} color="var(--state-error)" />,
   [RunningStatus.CANCEL]: <RefreshCw size={14} color="var(--accent-primary)" />,
   [RunningStatus.DONE]: <RefreshCw size={14} color="var(--accent-primary)" />,
   [RunningStatus.FAIL]: <RefreshCw size={14} color="var(--accent-primary)" />,

web/src/pages/dataset/dataset/use-dataset-table-columns.tsx

@@ -65,7 +65,8 @@ export function useDatasetTableColumns({
       header: ({ column }) => {
         return (
           <Button
-            variant="ghost"
+            variant="transparent"
+            className="border-none"
             onClick={() => column.toggleSorting(column.getIsSorted() === 'asc')}
           >
             {t('name')}
@@ -103,7 +104,8 @@ export function useDatasetTableColumns({
       header: ({ column }) => {
         return (
           <Button
-            variant="ghost"
+            variant="transparent"
+            className="border-none"
             onClick={() => column.toggleSorting(column.getIsSorted() === 'asc')}
           >
             {t('uploadDate')}